> One thing that I've always found contradictory in such
> discussions is the
> fact that it seems to be "...tribal knowledge" amongst
> Beverage aficianados
> that the WORSE the ground beneath it, the BETTER the
> performance of the
> antenna...
That isn't true. There is an optimum ground conductivity.
Above that value and below that performance declines.
Typical soils fall in the optimum range with a perfect
conductivity and perfect insulator grounds being the "poor
performance" extremes.
> ...And yet, Vic Misek in his book on Beverage antennas
> specifically espouses
> the use of a second parallel-running wire immediately
> below the antenna, per
> se, and laid atop the ground.
Nothing really prevents bad ideas from appearing in books.
The theory presented for using that wire falls apart for
multiple reasons.
> What purpose would the inclusion of such a ground wire
> have, in fact, if not
> to minimize the effect upon antenna performance by
> "...real ground"...?
It has no purpose in real life. If the ground is typical
soil and the wire is laid on the ground for several hundred
feet (even insulated) it provides virtually no path at all
for RF signals. There is far too much distributed loss.
If it did return the signals the antenna would simply quit
working as a Beverage. The signal from the return wire would
cancel the desired signals.
The claim it provides a "ground return" is obviously wrong.
If it actually provided a ground return the antenna would
not work as expected. Fortunately being coupled so closely
with lossy earth it has little effect, although any effect
it does have is NOT good.
73 Tom
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